Schweitzer Engineering SEL-351P, Quick Start Manual

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3-28 Overcurrent, Voltage, Synchronism Check, and Frequency Elements Date Code 990430
SEL-351P Manual Técnico
Settings Ranges
Table SECTION 3: .6: Negative-Sequence Time-Overcurrent Elements Settings
Setting Definition Range
51QP pickup 0.10 - 3.20 A secondary (1 A nominal phase
current inputs, IA, IB, IC)
51QC curve type U1 - U5 (US curves), C1 - C5 (IEC curves),
recloser or user curves
see Figure 9.1 - Figure 9.20
51QTD time dial (has no multiplying
effect on constant time adder
or minimum response time) 0.50 - 15.00 (US curves), 0.05 - 1.00 (IEC
curves), 0.10 - 2.00 (recloser or user curves)
see Figure 9.1 - Figure 9.20
51QRS electromechanical reset timing Y, N
51QCT constant time adder – adds
additional time to curve 0.00 - 60.00 cycles
(no effect if set = 0.00)
51QMR minimum response time –
flattens curve at set time;
curve can operate no faster
than this set time 0.00 - 60.00 cycles
(no effect if set = 0.00)
51QTC SEL
OGIC
Control Equation
torque control setting
Relay Word bits referenced in Table 9.3
or
set directly to logical 1 (= 1) or logical 0 (= 0)
– see note below
Note : If SEL
OGIC
Control Equation torque control setting 51QTC is set directly to logical 0
(i.e., 51QTC = 0), then corresponding negative-sequence time-overcurrent element 51QT
is defeated and nonoperational, regardless of any other setting.
See Section 9: Setting the SEL-351P Recloser Control for additional time-overcurrent element
setting information.
Accuracy
Pickup:
±
0.01 A secondary and
±
3% of setting (1 A nominal phase current inputs, IA, IB, IC)
Curve Timing:
±
1.50 cycles and
±
4% of curve time for currents between (and including) 2
and 30 multiples of pickup